Polymer flooding technology is useful for the recovery in the oil field and brings the serious problem of partial wear of sucker rod simultaneously. In this paper, the viscosity and rheological properties of poly produced fluid are investigated, and the computational fluid dynamics (CFD) method is used to simulate the rod tube annulus fluid flow. Through investigating the fluid resistance changed with the sucker rod movement speed, the water flooding calculation formula is fixed with the correction coefficient of 1.58. In addition, the resistance curve of liquid through traveling valve is piecewise fitted for the convenience of load calculation. Furthermore, the sucker rod loads are computed at total of 30 cases of 10 wells to shows the maximum deviations of the maximum and minimum load are 7.31% and 13.34% respectively, which shows a consistency between calculation and test. This study verifies the reliability of the calculation method and provides a foundation for wear preventing design of polymer flooding rod.